The invention relates to a method and an apparatus for producing patterns on substrates by coating the substrates spot-wise with a medium blocking a subsequent coating, and by the subsequent application of at least one functional coating.
U.S. Pat. No. 4,832,983 discloses a method for the metallization of plastic films, in which the film web is guided over a rotatable rubber roll whose cylindrical surface is provided with the desired relief pattern. The individual elements of the pattern raised above the cylindrical surface have an oil film on their surface which, by rolling on the film, produces the oil film imprints corresponding to the pattern. The film provided with the oil pattern is then passed over a cooled roll and at the same time vapor-coated, the metal vapor depositing itself on the oil-free areas of the film.
DE-OS 22 34 510 discloses a method for metallizing a film of insulating material serving for the manufacture of electrical condensers by continuous vapor depositing by the pass-through process. The elongated film wound on a roll is continuously unwound in an evacuated apparatus, carried past a source delivering the metal vapor in a vapor deposition area, and then rewound in the metallized state. The film unwound from the roll is introduced into the vapor deposition area in the preheated state.
DE-OS 21 12 405 discloses an apparatus for vapor coating a film intended especially for the manufacture of condensers having one or more metallized and one or more non-metallized longitudinal stripes. An oil vaporizer with one or more nozzles is disposed, as seen in the direction of movement of the film, ahead of an apparatus for vapor-depositing metal. The oil vaporizer has a base heater and at least one device for fast-response temperature control with a relatively narrow range of action, which is controlled according to the width of the non-metallized stripes on the film.
U.S. Pat. No. 4,478,878 discloses a method for the production of metal-free stripes in the vapor coating of a web of insulating material intended for use in electric condensers, wherein the insulating web is masked in the area of the metal-free stripes by an endless masking web running in contact with it at the same speed. Before entering the vapor-coating zone the masking web is coated with oil on the side facing the metal vaporizer. After passing through the vapor-coating zone, and after the separation of the masking web and the insulating material web, the masking web is wiped free of the vapor-deposited metal.
Lastly, U.S. Pat. No. 5,223,038 discloses an apparatus for the production of metal-free strips which has a hermetically sealable housing in which there is provided a system for receiving and driving a film web, especially for condensers. A vaporizing source with at least one nozzle discharges the substance to be vaporized to prevent condensation on the moving film web, the nozzle being formed of at least one opening extending approximately over the entire width of the film web.
The known methods and apparatus have the disadvantage that selectable patterns of separating agent cannot be printed on the films, or else the uniformity of the applied film of separating agent is inadequate, so that the contours of the areas on which the metal deposits itself lack sharpness. Also, there is no assurance that the parting agent will not wet additional areas of the film web which are to be coated with metal.